Time-domain numerical simulation of a flow-impedance tube

Ozyoruk Y. , Long L., Jones M.

JOURNAL OF COMPUTATIONAL PHYSICS, vol.146, no.1, pp.29-57, 1998 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 146 Issue: 1
  • Publication Date: 1998
  • Doi Number: 10.1006/jcph.1998.5919
  • Page Numbers: pp.29-57
  • Keywords: flow-impedance tube, computational aeroacoustics, impedance conditions, z-transforms, nonreflecting boundary conditions, finite difference, COMPUTATIONAL AEROACOUSTICS, BOUNDARY-CONDITIONS, SOUND


An efficient method has been developed for. the application of the surface acoustic impedance condition in time-domain solutions of aeroacoustic problems, such as the broadband-frequency simulation of a flow-impedance tube, The basis for this method is the standard impedance condition stated in the frequency domain as the particle displacement continuity equation. The development of the time-domain impedance condition follows the relations among the frequency. z-, and discrete-time domains and a rational function representation of the impedance in the z-domain. The resultant impedance condition consists of finite, infinite-impulse-response type, digital filter operations in the time domain, which is very suitable to computational aeroacoustics algorithms. This paper describes the present approach and discusses the time-domain numerical simulations of the NASA Langley how-impedance tube with a constant depth ceramic tubular liner. Both single and broadband-frequency simulations are performed. Excellent agreement is shown with experimental data at various frequencies and flow conditions. (C) 1998 Academic Press.